Also one more thing, I have an aftermarket headlights and front bumper, so the seams aren't exactly tight. So while at Menards I saw something that may work, flex PVC. Seen below. The size purchased will depend on the gaps that are being filled, but I picked up 1/2" OD, cost ~$2.00 for 10'.
And here's the gap to be filled, upper left of the headlight.
Now the nice thing about this PVC, is that is it is quite mailable and can be manipulated to fit the gap.
Nice, clean and cheap!
Now if your car isn't black like mine and you are worried about the color, pick up the clear type, you won't see it as much.